Known lawnmowers include a blade adaptor that is structured to secure a mower blade to the mower blade drive shaft of the lawnmower. Accordingly, mower blades are typically manufactured such that they are structured for use with a particular blade adaptor. One example of a blade adaptor and its corresponding mower blade can be found in U.S. Pat. No. 5,946,895 to Martens, which is incorporated herein in its entirety by reference thereto.